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2019.01.25 update

What is the cause of Flat battery?

Have you been experienced flat battery while you are driving? I would like you to talk about the cause of flat battery.



At first, I will tell about the function of battery. There are 3 main functions of battery as follow.


1. Start the starter motor
Motor vehicles use starter motors when starting vehicle engine. What is needed to start starter motor is electricity supplied from the battery. In other words, without a battery you cannot start the vehicle.


2. Supply power to electronic equipment when the engine is not running
 While an engine is running, a vehicle can produce electricity through an alternator mounted on the vehicle, however when the engine is running, only the battery can supply electricity to the car stereo, the power window, the light etc…


3. Charge the electricity while driving
The battery also can store electricity from the alternator after starting the engine or while the engine is running.

What is the Flat Battery?
Batteries are essentially storing cycles of electricity while the engine is stopped. However, if the amount of electricity stored in battery is not enough, the supply of electricity will be less than needed. Then it will be impossible to start the starter motor.



Symptoms of flat battery

1. Engine dose not start, driving noise is weak
It is the easiest to recognize that the engine will not start. Also, since the driving sound is also different from usual, it will be easy to tell. When you turn the engine key, usually you will hear starter motor is turning, then the engine will start. At this time, if the driving noise of starter motor is weaker than usual, it is hard to start the engine. There is possibility that the battery has flatted.


2. Electrical equipment such as power window, radio, etc. does not work
 Electrical equipment installed the car such as power window, radio etc. will move with the electricity from the battery when the engine is stopped. If the battery flatted, these electrical components will not work even if they are operated.



The reason why the battery goes to flat

1. Forgot to turn off the light
You may stop the engine and accidentally leave your car with the lights on. If you leave it like that for a long time, the battery will run out of electricity.


2. Spontaneous discharge
The battery of car causes a phenomenon called “Spontaneous Discharge”. Spontaneous Discharge is a phenomenon in which the amount of stored electricity naturally decreases little by little without using it. Normally, charging is carried out while driving, so this is no problem, but if you hardly drive the car for a certain distance, there is a possibility that the battery will go flat by Spontaneous discharge.


3. Luck of Battery Liquid
Inside the battery, liquid called battery liquid is contained. There is no problem if the battery fluid is properly filled with the prescribed amount. However, if you continue to use the battery with less battery fluid and the inner electrode plate exposed, the battery will be deteriorated and become easier to get flatted.



Periodic maintenance is necessary to prevent the battery from going flat. Your daily care will save your battery!



Japan Time